The pelargonium x domesticum [pe-lar-GO-nee-um] x [doh-MESS-tik-um] is more popularly known as Martha Washington geranium or regal geraniums.
This plant stands out in the geranium family thanks to its striking color pallet and foliage. You can add color to any garden with this bold plant.
While these annual geranium varieties are named after the wife of the first president of the United States, they are native to North Africa, with the first hybrids originating in Europe.
These bushy plants are commonly grown as annuals and tend to bloom in the later winter or early spring around Mother’s Day.
Martha Washington Geranium Quick Care Tips
- Botanical Name: Pelargonium domesticum
- Common Name(s): Martha Washington Geranium, Regal Geranium
- Synonyms: Pelargonium x domesticum, Pelargonium grandiflorum
- Family & Origin: Geraniaceae family, native to North Africa
- Growability: Moderate
- Grow Zone: USDA zones 5-10
- Size: Grows up to 2′ feet tall and wide
- Flowering: Blooms in the spring and summer with large, showy flowers in shades of pink, red, white, and purple
- Light: Needs bright, indirect light
- Humidity: Prefers moderate humidity levels
- Temperature: Thrives in temperatures between 60-70°F
- Soil: Well-draining soil with a pH of 6.0-7.0
- Water: Water when the top inch of soil is dry, but do not overwater
- Fertilizer: Use a balanced fertilizer every 2-3 weeks during the growing season
- Pests & Diseases: Susceptible to spider mites, whiteflies, and aphids. May also be prone to root rot if overwatered.
- Propagation: Propagated through stem cuttings or by division
- Plant Uses: Makes a great indoor or outdoor plant, can be used in containers or as a bedding plant.
If you want more color during the winter, you should learn how to care for this regal plant.
Martha Washington Geranium Care
How Big Do Martha Washington Geraniums Get?
The Martha Washington geranium can grow quite large. In fact, it can reach two feet in just one year.
You can grow these regal geraniums outdoors, but the plants are, first and foremost, indoor plants.
When grown outdoors, these geraniums typically only flower once and produce fewer flowers. NOTE: Wait until all danger of frost has passed when moving or planting outdoors.
They prefer well-drained soil. When the plant is young, you should use sandy soil. However, a mature Martha Washinton flower grows well in normal potting soil.
These plants are recommended for USDA hardiness zones 5 – 10, but the blooms tend to last longer in cooler environments.
If you decide to grow the regal geranium outdoors in a garden bed, space the plants at least 8” to 12” inches apart. When growing in a pot, the pot should be at least 8″ inches in diameter.
Don’t forget about drainage. The pot needs to have drainage holes to keep the soil from remaining too moist.
Flowering
While the plant can still grow quite large indoors, the showy flowers tend to get bigger when grown outdoors.
The benefit of growing indoors is that you can often “force” the plant to flower throughout the year.
The plant blooms from late spring until fall, producing large, colorful clusters of flowers with a wide range of sizes and hues.
The Martha Washington also grows crinkled dark green leaves on branching stems.
More Geranium Care Tips:
Bright Light and Temperature
The Martha Washington geranium requires plenty of sunlight. However, you should avoid direct sunlight. Moreover, this plant also grows well in light shade.
The main rule is to ensure that the regal geranium receives at least 6 hours of sun daily. If they don’t get enough light, the foliage will start to droop and wilt.
In the summer, keep the temperature in the low to middle 70° degrees Fahrenheit range and winter temperatures between 50° and 60° degrees Fahrenheit.
For container-grown plants, place them in window boxes or a sunny window to encourage blooms.
Watering and Feeding
Water regal geraniums frequently throughout the growing season.
During the summer, plants may need watering several times per week. Soak the root ball thoroughly.
When the plant starts to go dormant during the winter, you may only need to water it once or two every week.
Liquid fertilizer is recommended twice monthly during the summer if you want to produce large blooms and foliage. Adding a balanced all-purpose feed or granulated starter fertilizer can also give an extra boost.
Avoid high nitrogen fertilizers as they will encourage growth and not blooms.
However, this quick-growing plant doesn’t really need too much encouragement to grow.
Soil and Transplanting
The Martha Washington geranium grows best in well-drained soil. Regular potting soil is preferred. You can use any fertile, well-drained potting mix for the best results.
If you have a large geranium, repotting isn’t always easy. The best solution is to propagate the plant by taking cuttings.
If you do need to transplant a mature geranium plant, you should do so just before the summer in fresh soil, before the plant begins growing swiftly.
You should also trim it down and remove cuttings, which can be used for propagation.
Grooming And Maintenance
Grooming is recommended, as it helps increase the longevity of the plant. Removing spent or dead flowers helps produce more flowers and reduces disease as blossoms rot.
For more, read our article on Deadheading Geraniums
While regal geraniums can last for years, they tend to peak after three years.
Sooner or later, indoor geraniums will need cutting back as they grow larger and with an open, unshaped appearance.
Also, the geranium flowers begin to get smaller with weaker spindly top shoots.
This “look” means it is time to prune the plant. New shoots will appear, the plant will have a better bushy shape, and It will return to full flowering.
How to Propagate Martha Washington Geraniums
To propagate Martha Washington geraniums, you can take the cuttings in late summer.
Then, trim the plants back and use all the “not too woody” tip cuttings.
Four-inch tip cuttings with one or two pairs of leaves root best.
- Place cuttings in water or dip the bottoms into a hormone-rooting powder
- Pot cuttings in a well-draining sandy soil
- Cover pots with plastic bags (include some air holes)
- Cuttings should take root within two to three weeks
- Once rooted, plant the cutting into a new pot
Martha Washington Geranium Pests Or Diseases
Yellow Leaves – When the soil is too dry plants begin to exhibit yellow leaves and brown spots.
Remedy – Water thoroughly and monitor soil moisture.
Weak Growth – this usually shows up when plants do not get enough light.
Remedy – Move the plant to a better location with more light. Make sure the plant does get shade.
Learn more about Geranium Diseases here and Geranium Pests here.
Weak Basal Shoots – Bacterial infection can weaker plants.
Remedy – The best solution is to throw the plant away. DO NOT use the plants for cuttings.
Fungus And Rotting Stem – When plants are placed in damp, dark areas – they may experience fungus, and stems begin to turn dark and rot.
Remedy – Throw the plant away. DO NOT use the plants for cuttings.
“Balls Of Cotton” – When plants have white “balls of cotton” on leaves, and stem axils, expect to find mealybugs.
Remedy – Treat mealy bugs with Neem oil or Insecticidal soap.
Lots of leaves and not many flowers. Too much Geranium fertilizer. Plants are being overfed with high nitrogen fertilizer.
Remedy – Reduce fertilizer. Starve the plants a bit.
Master Growing Martha Washington Geranium
Martha Washington Geranium can be incredibly beautiful given the right conditions and is worth the effort to master its care.
Unlike other regal Pelargoniums, Martha Washington Geraniums are, first and foremost, an indoor plant that makes an attractive display on a porch, patio, or in a container.